Fluid dispensers, such as pump bottles, pump spray bottles, and in particular trigger sprayer bottles, are used to dispense a broad range of substances. Those substances include hand, face, and body lotions; and, cleaners for materials as diverse as wood, glass, vinyl, leather, suede, metals (such as aluminum, copper, brass, silver, and chrome), rubber (such as automobile tire brighteners), formica, ceramics, stainless steel, fabrics, painted surfaces, and the like.
The most commonly used type of fluid dispenser is probably the trigger-type sprayer bottle. (See, for example, TADA, U.S. Pat. No. 4,815,663, and European Patent Application No. 83110619.0, Publication No. 0 117 898, for illustrations and discussions of trigger-type sprayers.) Trigger-type sprayer bottles, while differing in specifics, generally share certain elements in common. Among these common elements are three referred to, for purposes of the present application, as the spinner, the priming valve, and the compression spring, which is located between the spinner and the priming valve. For purposes of convenience, these three elements are referred to collectively herein as the "spinner assembly".
The prior art spinner assemblies complicate the manufacture of the fluid dispensing apparatus into which they are incorporated because they are internal to those mechanisms. This is true even of the prior art one-piece spinner assemblies, such as that shown in TADA, U.S. Patent No. 4,815,663, FIG. 4a. As may be clearly seen from FIG. 1 of TADA, during assembly of the fluid dispensing apparatus, spinner assembly 60 must be placed within nozzle 56. This has at least two disadvantages compared with a spinner assembly which could be assembled to the fluid dispensing apparatus externally. First, the internal placement will require more time on the part of the assembler, slowing production time and increasing production costs. Second, should the spinner prove defective during quality control testing, the fluid dispensing apparatus must be disassembled in order to replace the defective spinner assembly.
There is a third disadvantage to the use of internal spinner assemblies, which relates to the need to provide the user of the fluid discharge apparatus with more than one configuration of fluid output. With the general exception of lotions, fluid dispensers are typically used to dispense liquids such as cleaning solutions. Because of the varied environments in which such dispensers may be used, and the extremely wide range of surfaces to which they may be applied, it is generally considered desireable to enable the user to select between different configurations of the discharged fluid. Most commonly, this selection provides the user with a choice between the spray configuration described above, and a stream configuration wherein the fluid is projected from the dispenser in a substantially coherent, cylindrical stream.
The prior art demonstrates that numerous attempts have been made to provide suitable selector mechanisms. STOESSER et al., U.S. Pat. No. 4,463,905, is directed to a foam-spraying apparatus wherein a liquid is first ejected from a hand dispensing pump through an atomizing nozzle, forming a spray, and the spray thus formed is then passed through foam-forming means. The foam-forming means includes a housing and a screen, and is operatively associated with the dispensing pump by a snap-fit mechanism (see, e.g., column 4, lines 42 et seq.).
TADA, U.S. Pat. No. 4,350,298, is directed to an improvement in the nozzle cap of a foam dispenser, whereby the nozzle cap includes a plurality of arms forming an obstacle with which a liquid sprayed from an orifice of the foam dispenser collides. A plurality of foam outlet ports is provided between adjacent arms. The nozzle cap is moveable relative to the foam dispenser body between a sealing and a foaming position, and may be formed integrally with the foam dispenser nozzle through a hinge (see, e.g., column 3, lines 14 et seq., and claim 1).
DOBBS, U.S. Pat. No. 4,706,888, is directed to use of a rotatable nozzle cap having a plurality of longitudinal grooves which communicate with alternating radial and tangential channels. Rotation of the nozzle cap controls whether the fluid current passes along the longitudinal grooves and through the radial channels, producing a stream, or through the tangential channels, which impart a spin to the fluid current and produce a spray.
Co-pending application U.S. Ser. No. 07/533,454, filed June 5, 1990, is directed to a fluid discharge apparatus for imparting a stream configuration to a current of fluid, in the form of a nozzle containing a passageway having at least a receiving portion with a substantially rectilinear cross-section, and an issuing portion with a substantially curvilinear cross-section. A fluid current passing through the passageway thereby emerges from it in a stream configuration. In a preferred embodiment, this apparatus may take the form of a cover or cap, hingedly connected to the discharge orifice region of the sprayer so that it can be reversibly attached to that orifice.
These selector mechanisms must cope with the fact that the initial fluid configuration which they are designed to change is generated by an internal mechanism, namely, the internally-mounted spinner assembly. Thus, at the point at which the selector mechanism acts to change the fluid configuration, the fluid has already passed beyond the spinner assembly and through the discharge orifice. Much of the prior art therefore provides a selector mechanism in the form of some type of cover or cap which may be reversibly attached to or placed over the discharge orifice. This increases the number of parts used in the fluid discharge apparatus, with a consequent increase in production costs and time; complicates operation of the apparatus by the user, who must generally manually engage or disengage the selector mechanism in addition to unsealing the discharge orifice; and, any such selector mechanism is likely to decrease the force with which the fluid is projected onto the work area. Moreover, the design and efficiency of such selector mechanisms is complicated by the need to make the selector mechanism fluid-tight when it is in operation.
Also of interest in this field is TADA, U.S. Pat. No. 4,940,186. As shown, for example, in FIGS. 13, 16, 20, and 21, this document discloses a spinner 112 which consists of a bottomed hollow cylinder (see also claim 6). Through holes are cut into the rear surface of the bottom of the spinner to form liquid passages 114. These liquid passages 114 communicate with a circular recess, 118, which is made in the center of the distal end of the spinner, through tangential grooves 115. As described at for example, column 14, lines 7-28, in use pressurized liquid flows from nozzle 79 through liquid passages 114 and into recess 118. There are at least two drawbacks to this configuration. First, and with particular reference to FIGS. 16 and 20, even with the cap 110 in the spray position wherein inner cylinder 122 of the cap is slightly moved away from the bottom of circular recess 118, fluid will not flow exclusively through tangential grooves 115 into circular recess 118 before exiting through orifice 113. Because of the clearance between the side wall of cylinder 122 and the side wall of circular recess 118, some fluid will also flow through liquid passages 114, into the gap between the front inner face of cap 110, and from there between the side wall of cylinder 122 and the side wall of circular recess 118, and thus into the circular recess. This will create significant turbulence in the circular recess, which may be expected to detract from the consistency of the resulting spray and/or to cause dripping at the outer opening of orifice 113. Second, because the fluid flows from the relatively large interior space of the bottomed hollow cylinder into relatively restricted liquid passages 114, and then directly through tangential grooves 115 and into circular recess 118, the fluid will have a relatively high velocity throughout its course from liquid passages 114 into circular recess 118. This will aggravate the turbulence problem referred to above, resulting in a correspondingly greater deterioration in spray quality and increased dripping.
In view of the above, it would be desireable to provide a spinner assembly which may be simply and efficiently assembled to a fluid dispensing apparatus from the exterior, and which may also cooperate directly with a selector mechanism, thereby simplifying production and use of the fluid dispenser while enhancing efficiency of operation and ease of use. It would also be desireable to provide a spinner assembly wherein the flow of pressurized liquid into the swirl chamber is controlled in a way which minimizes turbulence, thereby improving the characteristics of the output from the fluid dispensing apparatus and minimizing or even substantially eliminating dripping from the discharge orifice during use.